Lu AF28996 in Participants With Parkinson's Disease (PD)

Inclusion Criteria:

• Participants diagnosed with idiopathic PD (consistent with the UK PD Society BrainBank Criteria for the Diagnosis of PD), with not more than 1 first-degree relativewho has PD.

• Participants must have a Modified Hoehn and Yahr score ≤4 in the OFF state and ≤3 inthe ON state, and a Mini Mental State Examination score >25.

• The OFF/ON amplitude on the MDS-UPDRS Part III at screening must be minimum 30%difference.

• Participants must experience recognizable and predictable motor fluctuations (withat least 1.5 hours of OFF periods in the awake time, including predictable morningOFF episodes), causing clinically significant disability during the 7-week ScreeningPeriod, as evaluated by the investigator. This will be documented using aparticipant ON/OFF state registration over 3 consecutive days prior to enrolment.

• Allowed concomitant medication for PD during the study includes levodopa, monoamineoxidase B inhibitors, COMT inhibitors, anticholinergics, and amantadine. Dopamineagonists are not allowed and should be discontinued ≥4 weeks prior to dosing with LuAF28996 and until the end of the study.

• Participants diagnosed with idiopathic PD (consistent with the UK PD Society BrainBank Criteria for the Diagnosis of PD), with not more than 1 first-degree relativewho has PD.

• Participants must have a Modified Hoehn and Yahr score ≥2 to ≤4 in the OFF state and ≤3 in the ON state, a MDS-UPDRS Part IV, 4.5 score of 1 or 2, and a MDS-UPDRS PartIV, 4.2 score ≥2 (at least mild functional impact), and a Mini Mental StateExamination score >25 at the Screening Visit.

• Participants must currently have a good response to levodopa and be receiving astable dose of levodopa (≥3 doses per day of levodopa/dopa decarboxylase inhibitortherapy or ≥3 doses per day of levodopa Extended-Release Capsules and LEDD between 400 and 1600, inclusive) for at least 4 weeks prior to screening.

• Participants must experience recognizable and predictable motor fluctuations (with ≥3 hours of OFF periods in the awake time, including predictable morning OFFepisodes), causing clinically significant disability during 3 months prior toenrolment, as evaluated by the investigator. The criteria will be documented usingHauser Diary over 3 consecutive days prior to enrolment.

• Participants must experience ≥1 hour daily ON time with troublesome dyskinesia (TD)in the awake time (TD/24 hours while awake) during the last 3 months prior toenrolment as evaluated by the investigator. The criteria will be documented usingthe Hauser Diary over 3 consecutive days prior to enrolment.

• Allowed concomitant medication for PD during the study includes levodopa, dopamineagonists, if allowed daily dose, monoamine oxidase B inhibitors, COMT inhibitors,anticholinergics, and amantadine.

Exclusion Criteria:

• The participant has or had one or more of the following conditions that areconsidered clinically relevant in the context of the study; other neurologicaldisorder, psychiatric disorder, seizure disorder or encephalopathy, respiratorydisease, hepatic impairment or renal insufficiency, metabolic disorder,endocrinological disorder, haematological disorder, infectious disorder, anyclinically significant immunological condition, or a history of narrow-angleglaucoma.

• Participant has been treated with apomorphine (pen/pump), and/or inhaled levodopaand/or levodopa/carbidopa intestinal gel (LCIG),and/or subcutaneousfoslevodopa/foscarbidopa within 6 weeks prior to the Baseline Visit.

• Participants formerly treated with oral or transdermal dopamine agonists must havediscontinued 4 weeks prior to screening.

• Participant has a history of Dopamine Agonist Withdrawal Syndrome (DAWS) whendopamine agonists were previously discontinued or reduced.

Other inclusion and exclusion criteria may apply.